Telephone system.



No. 897,242. PATENTED AUG. 25 1998.

H. G. WEBSTER.

TELEPHONE SYSTEM.

APPLICATION FILED JULY 19, 1906. RENEWED JULY 6, 1908.

' 2 SHEETS-SHEET 1.

Q -ii i l hhl l H Q 4 M/Mwm PATENTED AUG. 25, 1908.

H. G. WEBSTER.

TELEPHONE SYSTEM.

APPLICATION FILED JULY 19. 1906. RENEWED JUL! 6, 1908.

2 SHEETS-$513131 Z.

1 0 a 0 iii?? iw/mv flwy slow Mn Fi o.

tgi [gangs ffiARRY Cr. WEBSTER, OF OEI-GAGO, ILLINOIS, ASSIGNOR TO MILO G. KELLOGG, OF CHICAGO,

ILL-3116018.

senate,

Ilo all whom it may concern. Be it known that I, HARRY 'Wnns'ram residing in Chicago, county of Cook, and State "of Illinois,- have invented new and use-- lrnprovements in Telephone Systems, of which the following is, a specification.

. "My invention relates to telephone ex.- charige systems 'and more particularly to systems of that type in which current for transmission-andsignaling is supplied to the substation from a central source through. the

windings of an electroinagnet, this magnet being connected with the telephone line normally andduring conversation. This electromagnet is preferably relay magnet and serves to partially control the signals associated with theline.

"The principal object of the invention is to provide novel means-wherehythe Winding or windings of the electromagnet may be dis connected from. the line when a ringing sig rial is to be actuated the susstation, thus preventingthe shunting of the ringing cur rent through the'magnet winding or the display of false signals through the energization ofthe magnet by-the ringing current.

l urther objects of my invention will be apparent from the following description.

' In accordance with my invention 1 associ ate with each line circuit a so-called double acting relay. Relays of this, type are characterized by the fact that their contacts have two operative positions other than normal, the two positions being controlled by energizing currents or" diilerent Value or character. This relay is utilized when actuated by what may be called its normal energizationyto control at one point the circuitof a calling signal from the subscriber, and it may be also utilized to control the display of a supervisory signal after connection ismade toa spring-jack of the line. the ringing signal is to be actuated at the substation, means are provided for securing an abnormal energization of the relay and in response to this abnormal energization, the relay controls contacts which serve to interrupt'the normal battery connection of the line. limbs, and thus leave one or both line limbs J free from earth connections and preventingany interference from this cause with the signal.

The invention will be more fully understood from the accompanying drawings forming a part of this specification in which Specification of Letters Patent.

he of any preferred type,

When

Patented ring; as, 190s.

Serial 1%. 442,247.

Figure l'illustrates two subscribe-rs lines. organized in accordance with areferred form of my invention. These ines are shown as terminating at a. central oflice and there associated with appropriate cord con necting apparatus. In this diagram, the

double-acting relay also serves as a line relay to cause the display of signal at the central oilice when circuit is closed at the substation. l i 2 is a diagram illustrating a modification of Fig. l in which the doulole acting line relay serves also tocontrol the display of a supervisory signal, andin which the 'springjacks or connection terrninals 'ior the line are provided 'ith three contact nieces instead of two as in Fig. 1. Fig. 3 illustrates a modification ofthe structure of Fig. 2 in which the ordinary line relay is pro vided, and in which a double-actingcut-ofl relay in a local circuit serves normally to conthe circuit of the line signal and ahnor inally to con rel the connections of the line relay to the line lirnhs. t illustrates a structure different from that of Fig. 3 in that the douhle-acting relay is a polarized. relay and is operated by currents of op osite polarity rather than by currents or different strength as in Like characters refer to corresponding parts in the several figures. I Referring to Fig. 1, A and indicate the two substations which are connected to the central office by suitable telephone lines. The equipment at the substations, which may is here shown as comprising a condenser c and a ringing signal or call bell-b normally in bridge of the line limbs and a receiver r and, transmitter 15 in an alternate bridge of the line limbs adapted to be closed at the upper contact of the hook switch h. At the central office a relay 3 is provided having two windings. Its contacts are so arranged that when the relay is energized by a relatively Weak current, a circuit will be closed at armature 9 and contact 8, but the connection indicated at armature 6 and contact 7 will remain uninterrupted. When the relay is energized bya relatively strong current',-hoth sets of contactsm'will be actuated and winding 4 thus disconnected from limb 1 of the line. When the. sub scriber at'substation A; desires to initiate a call and removes his receiver from its switch hook, current'will low from the intermediate terminal of battery C through winding 4,

' ground.

contact 7, armature 6, limbsl and 2 and winding 5, through the ground or return side of the battery. .This current is of relatively low voltage and will produce a normal energization of the relay, and the resulting attraction of armature 9 completes a current for lamp 1.0 through contact/8, and through contact H and armature 13 of relay 11, thus indicating to the operator that a connection is desired. Upon insertion of the connecting plug 0 into the jack j of the calling line, current will flow from the intermediate terminal of battery (I through relay 24, strand 20 of the cord circuit, contact 16, winding 12 of relay 11, and winding5 of relay 3 to A current. will also flow through relay 23, strand 19, contact 17 of the springjack, winding 15 of relay 1-1, and thence through the line limbs and winding 5 to ground. This current serves to energize relay 11 and the energization of relay 23 serves to prevent the display of the supervisory lamp 27 which would otherwise have its circuit completed at the contacts of relay-24. The energization'oi relay 11 serves to extinguish lamp 10by opening its circuit at. arm ature 13 and contact 14, and armatureti of relay 3 remains in its normal position at this time. The operator actuates her-listening key 70 and after learning with what line con.

'nection is desired, in this case that of subscriberB, she tests in the usual way. If the line beidle, contact 16 of the jack will be at the potential of the grounded side of the battery and'no current flow will result. If the line be busy, the contact16 then being connected with an active terminal of the battery through the sleeve strand of the connected. cord circuit, current will flow when the test is made,'irom contact 16 through strand 21, armature 30 of relay 26, its normally closed contact and to ground through the common test relay 31, and the resulting energization oi relay 31 closes a circuit of battery C through the test winding of the operators induction coil, thus giving the required indication. Assuming that the line be idle, the operator inserts the connecting plug P and actuates her ringing key 7c. A circuit may then be traced from'the upper terminal of battery C through resistance 32, contact 16, winding 12 and vthruughwinding 5 of relayB to ground. This current being of higher potential than that which isnormally supplied. to relay 3, causes the'actuation of both of its armature contaots'and' also energizes relay 1 1; The ac' tuation oi armature 6 disconnects winding 4 of relay 3ffrorn limb 1 of the line, thus leavill-g thatflimb free from battery or earth connections andtheeiier ization of relay 11 prerents the display 0.5 amp 10, by the interruptijen er its" circuit at contact 1.- -1.- A an suit infringing 'eur'rent -may then be traced frQmgpnerater through ctmtaet 17 or saming 'taeic winding L54: limbs .1 and. '2 andto v and armature 9 of relay 3.

the

ground through winding 5 of relay 3 or through Winding 12, contact 16, resistance 32 and the sections of the battery C. Upon the restoration of the ringing key, current flows from the intermediate terminal of the battery through relay 26, strand contact 16,

winding 12 and winding 5 to ground. This current being of relatively small value, arma ture 6 of relay 3 returns to its normal position and the e'nergization of relay 1 1 prevents. the display otlamp 10. The energization of relay 26 at this time completes the circuit of s11- pervisory lamp 28 at armature 29 and the attraction of armature 30 disconnects thet'est relay 31 and completes the talking-circuitof strand 21. When the. subscriber answers, current will flow through relay25, strand 21, contact 17,-winding 15, limbs 1 and 2,, and to ground through winding 5 of relay 3, thus energizing the substation transmitter and causing relay 25 to interrupt the circuit of lamp 28. T he two subscribers are now unitedfor conversation and when either replaces his re ceiver, the 'eonsequent interruption of the circuit of relay 23 or 25 causes the illumination of the corresponding supervisory lamp and the display of both lamps constitutes the usual disconnect signal. It. is to be noted that the relay 11 is indicated as having twinwind ings and these windings being differentially connected, no undue interference with the transmission of voice currents results therefrom. '7 The structure of Fig. 2 diii'ers from that of Fig. 1 in that the spring-jacks and connecting plugs are provided with three contact pieces eacl'i, instead of two, and in that the operation of the supervisory lamps is contr 1 lled by contacts of relay 3.1'ather than by relays associated with the cord circuit. When the subscriber calls, the ensuing normal en'ergization of relay 3 causes the attraction of armature 9, thus closing a circuit for lamp 10 which may be traced from the active terminal of battery C through lamp 10, armature 36 and contact of relay 34 and through contact 8 Upon the insertion of an answering plug 0, current flows through lamp 27, contact 37 of the springjack, and to ground through the-winding of relay 34. Theresistance of the Winding of relay 34 is so pro )ortioned that-although the relayis energize the current flow is not sufiicient to sense the illumination of lamp 27. The energization of the relay serves to interru pt the circuit oi lamp 10 at armature 36. When the subscriber has finished conversation and replaces his receiver, the resultingdeenergization of relay 3 allows armature .9." to engage contact 33, thus completing slower resistance circuit to ground for lamp .27 through resistance 47 and the resulting-Tenn rent is sufficient to illuminate lampl27. The" value of resistance 4'? is such that when eonneetion is made'to a spring-jack of the tine to its call the subscriber, the electrical potential at ground. Battery C the necessary busy test. When it is desired to call the subscriber, the calling lug P is inserted into the springjack and the ringing key 75 is actuated and circuit is thus completed from battery C through resistance 32, strand 2-1, contact 17 and winding 5 to being of relatively greater voltage than C, the relay is at this "time energized toits greatest capacity and the consequent attraction of armature 6 disconnects winding 4 from limb 1, thus leaving limb 1 clear for ringing current from generator G. When the ringing key is restored,

the relay 3 assumes its normal'position, the p supervisory lamp28 being then lighted by current flowing through resistance 47 and relay 34, and when the subscriber answers, the attraction of armature 9, causes the extinguishment of supervisory lamp 28 and the energization of relay 34 prevents the display of the line lamp 10.

' Fig. 3 is a diagrammatic illustration of a structure dil'l'ering from that of Fig. 2 in that a double-acting relay 39 is substituted for relay 34 of the former diagram, the line relay 48 being of ordinary construction. When the subscriber calls, current flowing through windings 4 and 5 of relay 48 and through armature contacts 42 and 43 of relay 39, closes the circuit of lamp 16 at armature 9 contact 8 and through armature 51.. Upon the insertion of the answering plug, current will flow from battery C through lamp 27, contact 37 and through winding ofrelay 39 to ground. This current is of relatively small value and suihces only to cause the attrac tion. of armature 51, thus extinguishing the lamp 1.0. W hen the subscriber is to be called, the actuation of ringing key 76 completes a circuit for battery which may be traced from the upper terminal of the battery through contact 46 and lever 45 of the ringing key, and thence through contact 57 of the plug, contact 37 of the jack and to ground through the winding of relay 39. Battery 0 being of relatively high voltage, the ensuing energization of relay 39 is suflicie-nt to cause the complete attraction of armature 51.. This action prevents the display of line lamp 10, disconnects the windings 4 and 5 of relay 48 from the line limbs at armature contacts 42 and 43 and the' engagement of contact 42 with contact 41 completes a circuit for windings 4 and 5 to hold armature 9 out of engagement with contact 33 and thus prevent resistance 40 from shunting relay 39. It is also to be understood that when the ringing key is actuated, current from generator G will momentarily flow through windings 4 and 5, thus breaking the circuit'through resistance 40 during the initial energization of relay 39.

' Upon the restoration of the ringing key, contacts 42 and 43 assume their normal positions plug contact 57, jack traction of in'mature 51.

that and the current whi h then flows from battery C through lamp 28, contact 44, lever 45, contact 37 and through resistance 40 and relay 39, is sufiicient to illuminate ls1np28 and causes the partial at- "When the subscriber answers, the resulting energization of relay 48 interrupts the path icrsummit through resistance lamp 28, as in Fig. 2.

' Fig. '4 differs from Fig. '3 in that a polarized relay 49 is provided in place of the doubleacting relay 39. This relay is normally-en- 40 and thus extinguishes I ergized by current from the upper terminal of battery C the current then being in-the roper direction to cause the u per end of arto the rig t, thus interrnature 50 to move lamp 10 at contact 56.

rupkting the circuit of W en the ringing key is subscriber, current then flows from the lower terminal of battery C and causes the upper end of armature 50 to move to the left, thus,

' disconnecting windings 4 and 5 of relay 48 from limbs 1 and 2, at contacts '52 and 53. The control of the line lamp and supervisory lamp is otherwise as described in connection with Fig. 3.-

It is to be understood that the illustrations actuated in calling a of the double-acting relays in the several figures are diagrammatic illustrations only, that any preferred mechanical structure may be employed. It is also to be understood the several batteries, illustrated may be arranged as one common battery having several connection terminals or in any way desired, and that the several grounds indicated may be connections to the office return. It will also'be apparent that the ringing signal at the substation may consist of any suitable electrical device other than the call cell 1), and that many alterations and modifications of my invention may be made without departing from its spirit, and ii therefore, de not Wish to be limited to the precise structures illustrated. 7

That which I consider as new and novel and desire to secure by Letters Patent of the United States, is

li A telephone exchange system comprising a telephone line extending vfrom a substation to the exchange, a telephone transmitter and a ringing signal at the substation, a source of r nging current at the exchange,'a switch for connectin said ringing source to the line, a signal indicator at the exchange partially controlled from the substation, an energizing circuit for the transmitter completed through a normal connection of the ne, and means for interrupting said normal connection during the connection of said ringing source.

2. A telephone exchange system comprising a telephone line extending from a substation to the exchange, a telephone transmitter and a ringing signal at the substation, a

and

source of ringing current at the exchange, a switch for connectin said ringingsource to the line, a signal ind icator at the exchange partially controlled from the substation, an energizing circuit for the transmitter com- ;leted through a normal connection of the line, and a-relay for interrupting said normal connection during the connection of said ringing source.

A telephone exchange system comprising a telephone line extending from asubstation to the exchange, a telephone transmitter and a ringing signal. at the substation, a source ot ringing current at the exchange, a switch for connecting said ringing source to the line, a signal indicator at the exchange partially controlled from the substation, an energizing circuit for the transmitter comleted tln'ough a normal connection of the line, and a double-acting relay for interrupting said normal connection during the connection of said ringing source.

4. A telephone exchange-system comprise-- ing a telephone line extending from a suhsta' tion to the exchange, a telephone transmitter and a ringing signal at the substation, source of ringing current at theexchange, a, switch for connecting said ringing source to the line, a signal indicator at the exchange I partially controlled from the substation, an energizing circuit for the transm tter come @leted through a normal connection of the line, and a cut-ofi' relay for interrupting said normal connections during the connection of said ringing source.

A. telephone exchange system compris ing a telephone line extending from a substation. to the exchange, a telephone'transinitter and a ringing signal at the substation, a source of ringing current at the exchange, a switch for connecting said ringing source to the line, signal indicator at the exchange partially controlled from the substation, an

energizing circuit for the transmitter comleted through a normal connection of the inc, and-a double-acting cut-01: relay for interrupting said normal connection duringthe connection of said ringing scrzrce. 6. A teleohone exchange system comprising a telephone line extending from a substation to the exchange, a telephone transmitter and a ringing signal at the substation,

a source of ringing current at the exchange, a

switch for'connectin said ringing source to the line, a signal n1 icator at the exchange partially controlledfrom the substation, an'

energizing circuit for the transmitter completed. through a normal connection of the line, and means normallyoperating to partially control the display of the signal indigator. and abnormally operated to interrupt said normal-connection during the conncction of said ringing source. 7. .A telephone exchange system comprisa asap-abusin extending frorn a: sub.

station to the exchange, a telephone trans mitter and a ringing signal at the substation,

- a source of ringing current at the exchange, a

switch for connecting said ringing source to the hue, a signal indicator at the exchange partially control ed from the si'ibstation, an'

energizing circuit or the transmitter completed through a normal COIlIlG-CUOH of the me, and a rclaynormally opcratingto' partially control the display of the signal indicater and abnormally operated to'interrupt' said normal connection durlng the connection of said ringing source.

8. A telephone exchange system-comprismg a telephone line extending from a sub- 'station tothe excha.nge, a telephone transmitter and a ringing signal. at the substation,

a source of ringing current at the exchange, a switch for connecting said ringing'sou'rce to the line, a signal indicator atthe "exchange partially controlled from the substation, an

energizing circuit for the transmitter com-.

leted through a normal connection-of the ins, and a cut-off relay normally operating to partially control the display of the signal indicator and abnormally operated to inter rupt said normal connection during the con nection of said ringing source.

-9. A tele hone exchange system compris ing atelep ione line extending from a substation to the exchange, a telephone transmitter-and a ringing signal at the substation,

a source ofringing'current atthe exchange,

a switch for connecting said ringing source to the line, a signal indicator at the'ex'change partially. controlled from the substation, an energi'zlng circuit for the transmitter-comleted through a normal connection-of the ine, and means controlled by theactuation of said switch for temporarily interruptingsaid normal connection during the connection of said ringing source.

10. A telephone exchange system comprising a telephone line extending from a sub station to the exchange, a telephone transmitter and a ringing signal at the substation, a source of ringing current at the exchange, a

'. switch for connecting said ringing source to switch for connecting sai'd'ringing source to the line, 'asignal indicator attherexcha'nge partially controlled-from the substation, an

energizing-.circurt ior--the' trans1nitte1f comrupting said normal connection during" the connection ofsaid ring ng source;

12. A telephone exchange system comprising a telephone 11118 extending from a substation to the exchange, a telephone transmitter and a ringing signal at the substation, a

source of ringing current at the exchange, a switch for connecting said ringing source to the line, a signal indicator at the exchange partially controlled from the substation, an energizing circuit for thetransmitter comleted through a normal connection of the inc, and a cut-ofi relay controlled at contacts of said switch .for temporarily interrupting said normal connection during the connection of said ringing source.

13. A telephone exchange "system comprising a telephone line extendin'g from a substation to the exchange, a telephone transmitter and a ringing signal at the substation, a source of ringing current at the ex change, a switch forconnecting said ringing source to the line, a signal indicator at the exchange partially controlled from the substation, an energizing circuit for the transmitter completed through a normal connection of the line, and a double-acting cut-oil relay controlled at contacts of said switch for temporarily interrupting said normal connection during the connection of said rmgmg 0 pleted.

14. A telephone exchange system comprising a telephone line extending from a substa-- to interrupt said normal connection during the connection of said ringing source.

15. A telephone exchange system comprising a telephone line extending from a substation to the exchange, a telephone transmitter and a ringing signal at the substation, a source ofiringing current at the exchange, a switch for connecting said ringing source to the line; a signal indicator at the exchange partially controlled from the substation, an energizing circuit for the transmitter comthrough a normal connection of the line, and a relay normallyoperating to partially con rol the displayof the signal indicator and abnormally operated by current in a circuit controlled at contacts of said switch to interrupt said normal connection during 'the connection of said ringing source.

16. A telephone exchange system comprismga telephone line extending from a substation to the exchange, a telephone transmitter and a ringing signal atjth'e substation, a source of ringing current at tie exchange, a switch for connecting said ringing source to the line, a signal indicator at the'exchange partially controlled from the substation, an

energizing circuit for the transmitter completed through a normal connection of the line, and a cut-oft relay normally operating to partially control the display of the signal indicator and abnormally operated by current in a circuit controlled at contacts of said switch to interrupt said normal connectioh during the connectionof said ringing source.

175A telephone exchange system comprising a'telephone line extending from a substation tothe exchange, a ringing signal at the substation, a source of ringing current at the exchange, a switch for-connecting said ring-.

ing source to the line, a signal controlling electromagnet at the exchange said magnet being individual to the line and in circuit therewith during conversation, and means for interrupting the circuit of said magnet during the connection of said ringing'source to the line. 7

18. A telephone exchange system comprising a telephone hne extendmg from a substation to the exchange, a ringing signalat the substation, a source of ringing current at the exchange, a'switch for connecting said ringing source to the line, a signal controlling electromagnet at the exchange said magnet being individual to the line and in circuit therewith during conversation, a central source for supplying talking current to con n, ted substations, and means for preventing the actuation of said magnet by current from said ringing source during the connection of said ringing source to the line.

19. A telephone exchange system comprising a telephone line extending from a substation to the exchange, a ringing signal at the substation, a sourcevof ringing current at the exchange, a switch for connecting said ringing source to the line, a signal controlling electromagnet at the exchange said magnet being individual to the line and in circuit therewith during conversation, and means controlled through the actuation of said switch for interrupting the circuit of said magnet during the connection of said source to the line.

20. A telephone exchange system comprising a telephone line extending from a substation to the exchange, a ringing signal at the substation, a source of ringing current at the exchange; a switch for connecting said ringing source to the line, a signal controlling electromagnet at the exchange said magnet being individual to the line and in circuit therewith during conversation,. a central source for supplying talking current to connected substations, and means controlled through the actuation'of said switch for pi'eventing the actuation of said magnet by currentfrom said ringing source during the connection of said ringing source to the line.

21. A telephone exchange system comprising a telephone line extending from a sub station to the exchange, a ringing signal at the substation, a source of ringing current at the exchange, a switch forconnecting said ringing source to the line, a signal controlling electromagnet, at the'exchange said magnet being individual to the line and in circuit therewith duringconversation, and means controlled at contactsof said switch for in-- 'tcrrupting the circuit of the magnet during the connection of said source to the line.

22. A telephone exchange system comprising a telephone line extending from a sub; station to the exchange, a ringing signal at the substation, a source of ringing current at the exchange, a switch for connecting said ringing source to the line, a signal controlling electromagnet at the'exchange said magnet bein g individual to the line and in circuitth erewith during conversation, a central source .for supplying talking current to connected.

switch for connecting said ringing source to the line, an energizing circuit for the transmitter completed through a normal connec-' tion of the line, and means forinterrupting said normal connection during the connection of said ringing source.

24. A telephone system comprising a telephone line extending from a substation to' a central office, a line relay having a plurality therewith, resistance devices associated with said line, means for connectiiig said supervisory lamp in series with parallel branches each including one of said resistance devices,

and contacts on said line relay for controlling the continuity of one of said branches, whereby the lighting and extinguishing of said supervisory lamp during the connection of said cord-circuit and line is under the control'of the subscriber. g

25. A telephone system comprising a telephone line extending from a substation to a central otlice, a line -relay having a plurality of windings, means normally under the con- .trol of the subscriber for closing a circuit through both of said windings to energize said relay, a line signal having a circuitnormally open only at said relay and therefore displayed in response to such energizat-ion, means tortlisconnectmg one of said line relay windings from its line limb by supplying current to the other winding, a cord-circuit, a supervisory lamp associated therew1th, 'a cutoff relay for controlling said line signal cir cuit, a resistancecoil, said cut-oit relay and resistance coil being in parallel branches,

means for connecting said supervisory lamp in circuit with said cut-off relay and res1st ancecoil, and contacts onsaid line relay-for controlling the continuity of the branch including said resistance coil, whereby the supervisory lam and extinguis branch p v y In witness whereof, I hereunto subscribe my name this 17th day of July 1906.

HARRY tag-WE STER.-

ed by the opening of said *Witnesses ALFRED H. DYsoN, Gno. MUELLER.

will be lighted by the -closing} 

